Calculations in place

app/scripts/app.js

@@ -33,9 +33,25 @@ angular
       // set app to have pretty URLS
 			$locationProvider.html5Mode(true);
   })
-  .controller('MainController', function() {
+  .controller('MainController', function($scope) {
 		var vm = this;
-		vm.og = 1.06;
-		vm.abv = 7.77;
+		vm.reading = {}; // stores og, fg, abv
+
 		vm.message = 'To Alcohol the cause of and solution to all of life\'s problems!';
+
+		vm.abvFormula = function(readings) {
+			//  (  ( 1.05  x  ( OG – FG )  )  / FG  )  / 0.79  x  100 = % ABV
+			return (( 1.05 * ( readings.og - readings.fg )) / readings.fg) / 0.79 * 100;
+		}
+
+		vm.calculateABV = function() {
+			console.log(this.reading);
+			if(this.reading.og !== undefined && this.reading.fg !== undefined) {
+				this.reading.abv = this.abvFormula(this.reading);
+
+			}
+		}
+
+
+
 	});